Thermoset molding compositions known in the art are generally thermosetting resins containing inorganic fillers and/or fibers. Upon heating, thermoset monomers initially exhibit viscosities low enough to allow for melt processing and molding of an article from the filled monomer composition. Upon further heating the thermosetting monomers react and cure to form hard resins with high modulus.
There remains a need for thermoset compositions exhibiting improved combinations of properties including curing rate, toughness, stiffness, and heat resistance.
One embodiment is a composition comprising: a capped poly(arylene ether); an alkenyl aromatic monomer; and an acryloyl monomer. The present inventors have found that this composition provides a highly desirable combination of fast curing, reduced curing rate oxygen sensitivity, high toughness, high stiffness, and high heat resistance. At least one of these properties is compromised if any of the components is omitted.
Another embodiment is a method of preparing a thermoset composition, comprising: blending a capped poly(arylene ether), an alkenyl aromatic monomer, and an acryloyl monomer to form an intimate blend.
Another embodiment is a cured resin comprising the reaction product of: a capped poly(arylene ether); an alkenyl aromatic monomer; and an acryloyl monomer.
One embodiment is a thermoset composition, comprising: a capped poly(arylene ether); an alkenyl aromatic monomer; and an acryloyl monomer.
The composition comprises a capped poly(arylene ether), which is defined herein as a poly(arylene ether) in which at least 50%, preferably at least 75%, more preferably at least 90%, yet more preferably at least 95%, even more preferably at least 99%, of the free hydroxyl groups present in the corresponding uncapped poly(arylene ether) have been functionalized by reaction with a capping agent.
There is no particular limitation on the molecular weight or intrinsic viscosity of the capped poly(arylene ether). In one embodiment, the composition may comprise a capped poly(arylene ether) having a number average molecular weight up to about 10,000 atomic mass units (AMU), preferably up to about 5,000 AMU, more preferably up to about 3,000 AMU. Such a capped poly(arylene ether) may be useful in preparing and processing the composition by reducing its viscosity. In another embodiment, the composition may comprise a capped poly(arylene ether) having an intrinsic viscosity of about 0.15 to about 0.30 deciliters per gram (dl/g), preferably about 0.20 to about 0.25 dl/g, as measured in chloroform at 25xc2x0 C. Generally, the intrinsic viscosity of the capped poly(arylene ether) will vary insignificantly from the intrinsic viscosity of the corresponding uncapped poly(arylene ether). These intrinsic viscosities may correspond approximately to number average molecular weights of about 5,000 to about 25,000 AMU, preferably about 8,000 to about 20,000 AMU, more preferably about 10,000 to about 15,000 AMU. Such a capped poly(arylene ether) may provide the composition with a desirable balance of toughness and processability. It is expressly contemplated to employ blends of at least two capped poly(arylene ether)s having different molecular weights and intrinsic viscosities.
The capped poly(arylene ether) may be represented by the structure
Q(Jxe2x80x94K)y
wherein Q is the residuum of a monohydric, dihydric, or polyhydric phenol, preferably the residuum of a monohydric or dihydric phenol, more preferably the residuum of a monohydric phenol; y is 1 to 100; J comprises recurring units having the structure 
wherein m is 1 to about 200, preferably 2 to about 200, and R1-R4 are each independently hydrogen, halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbonoxy, C2-C12 halohydrocarbonoxy wherein at least two carbon atoms separate the halogen and oxygen atoms, or the like; and K is a capping group produced by reaction of a phenolic hydroxyl group on the poly (arylene ether) with a capping reagent. The resulting capping group may be

or the like, wherein R5 is C1-C12 alkyl, or the like; R6-R8 are each independently hydrogen, C1-C12 alkyl, C2-C12 alkenyl, C6-C18 aryl, C7-C18 alkyl-substituted aryl, C7-C18 aryl-substituted alkyl, C2-C12 alkoxycarbonyl, C7-C18 aryloxycarbonyl, C7-C18 alkyl-substituted aryloxycarbonyl, C7-C18 aryl-substituted alkoxycarbonyl, nitrile, formyl, carboxylate, imidate, thiocarboxylate, or the like; R9-R13 are each independently hydrogen, halogen, C1-C12 alkyl, hydroxy, amino, or the like; and wherein Y is a divalent group such as 
or the like, wherein R14 and R15 are each independently hydrogen, C1-C12 alkyl, or the like.
In one embodiment, Q is the residuum of a phenol, including polyfunctional phenols, and includes radicals of the structure 
wherein R1-R4 are each independently hydrogen, halogen, primary or secondary C1-C12 alkyl, C1-C12 alkenyl, C1-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 aminoalkyl, C1-C12 hydrocarbonoxy, C1-C12 halohydrocarbonoxy wherein at least two carbon atoms separate the halogen and oxygen atoms, or the like; X may be hydrogen, C1-C12 alkyl, C6-C18 aryl, C7-C18 alkyl-substituted aryl, C7-C18 aryl-substituted alkyl, or any of the foregoing hydrocarbon groups containing at least one substituent such as carboxylic acid, aldehyde, alcohol, amino radicals, or the like; X also may be sulfur, sulfonyl, sulfuryl, oxygen, or other such bridging group having a valence of 2 or greater to result in various bis- or higher polyphenols; y and n are each independently 1 to about 100, preferably 1 to 3, and more preferably about 1 to 2; in a preferred embodiment, y=n.
In one embodiment, the capped poly(arylene ether) is produced by capping a poly (arylene ether) consisting essentially of the polymerization product of at least one monohydric phenol having the structure 
wherein R1-R4 are each independently hydrogen, halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbonoxy, C2-C12 halohydrocarbonoxy wherein at least two carbon atoms separate the halogen and oxygen atoms, or the like. Suitable monohydric phenols include those described in U.S. Pat. No. 3,306,875 to Hay, and highly preferred monohydric phenols include 2,6-dimethylphenol and 2,3,6-trimethylphenol. The poly(arylene ether) may be a copolymer of at least two monohydric phenols, such as 2,6-dimethylphenol and 2,3,6-trimethylphenol.
In a preferred embodiment, the capped poly(arylene ether) comprises at least one capping group having the structure 
wherein R6-R8 are each independently hydrogen, C1-C12 alkyl, C2-C12 alkenyl, C6-C18 aryl, C7-C18 alkyl-substituted aryl, C7-C18 aryl-substituted alkyl, C2-C12 alkoxycarbonyl, C7-C18 aryloxycarbonyl, C7-C18 alkyl-substituted aryloxycarbonyl, C7-C18 aryl-substituted alkoxycarbonyl, nitrile, formyl, carboxylate, imidate, thiocarboxylate, or the like. Highly preferred capping groups include acrylate (R6=R7=R8=hydrogen) and methacrylate (R6=methyl, R7=R8=hydrogen).
In another preferred embodiment, the capped poly(arylene ether) comprises at least one capping group having the structure 
wherein R5 is Cxe2x80x94C alkyl, preferably Cxe2x80x94C alkyl, more preferably methyl, ethyl, or isopropyl. The present inventors have surprisingly found that the advantageous properties of their composition can be achieved even when the capped poly(arylene ether) lacks a polymerizable function such as a carbon-carbon double bond.
In yet another preferred embodiment, the capped poly(arylene ether) comprises at least one capping group having the structure 
wherein R9-R13 are each independently hydrogen, halogen, C1-C12 alkyl, hydroxy, amino, or the like. Preferred capping groups of this type include salicylate (R9=hydroxy, R10-R13=hydrogen).
In still another preferred embodiment, the capped poly(arylene ether) comprises at least one capping group having the structure 
wherein A is a saturated or unsaturated C2-C12 divalent hydrocarbon group such as, for example, ethylene, 1,2-propylene, 1,3-propylene, 2-methyl 1,3-propylene, 2,2-dimethyl-1,3-propylene, 1,2-butylene, 1,3-butylene, 1,4-butylene, 2-methyl-1,4-butylene, 2,2-dimethyl-1,4-butylene, 2,3-dimethyl-1,4-butylene, vinylene (xe2x80x94CHxe2x95x90CHxe2x80x94), 1,2-phenylene, and the like. These capped poly(arylene ether) resins may conveniently be prepared, for example, by reaction of an uncapped poly(arylene ether) with a cyclic anhydride capping agent. Such cyclic anhydride capping agents include, for example, acetic anhydride, methacrylic anhydride, acrylic anhydride, salicylic anhydride, succinic anhydride, glutaric anhydride, propionic anhydride, isobutyric anhydride, maleic anhydride, adipic anhydride, phthalic anhydride, and the like, and combinations comprising at least one of the foregoing capping agents.
In a preferred embodiment, the capped poly(arylene ether) is substantially free of amino substituents, including alkylamino and dialkylamino substituents, wherein substantially free means that the capped poly(arylene ether) contains less than about 300 micrograms, preferably less than about 100 micrograms, of atomic nitrogen per gram of capped poly(arylene ether). Although many poly(arylene ether)s are synthesized by processes that result in the incorporation of amino substituents, the present inventors have found that thermoset curing rates are increased when the capped poly(arylene ether) is substantially free of amino substituents. Poly(arylene ether)s substantially free of amino substituents may be synthesized directly or generated by heating amino-substituted poly(arylene ether)s to at least about 200xc2x0 C. Alternatively, if the capped poly(arylene ether) contains amino substituents, it may be desirable to cure the composition at a temperature less than about 200xc2x0 C.
There is no particular limitation on the method by which the capped poly(arylene ether) is prepared. The capped poly(arylene ether) may be formed by the reaction of an uncapped poly(arylene ether) with a capping agent. Capping agents include compounds known in the literature to react with phenolic groups. Such compounds include both monomers and polymers containing, for example, anhydride, acid chloride, epoxy, carbonate, ester, isocyanate, cyanate ester, or alkyl halide radicals. Capping agents are not limited to organic compounds as, for example, phosphorus and sulfur based capping agents also are included. Examples of capping agents include, for example, acetic anhydride, succinic anhydride, maleic anhydride, salicylic anhydride, polyesters comprising salicylate units, homopolyesters of salicylic acid, acrylic anhydride, methacrylic anhydride, glycidyl acrylate, glycidyl methacrylate, acetyl chloride, benzoyl chloride, diphenyl carbonates such as di(4-nitrophenyl)carbonate, acryloyl esters, methacryloyl esters, acetyl esters, phenylisocyanate, 3-isopropenyl-alpha,alpha-dimethylphenylisocyanate, cyanatobenzene, 2,2-bis(4-cyanatophenyl)propane), 3-(alpha-chloromethyl)styrene, 4-(alpha-chloromethyl)styrene, allyl bromide, and the like, carbonate and substituted derivatives thereof, and mixtures thereof. These and other methods of forming capped poly(arylene ether)s are described, for example, in U.S. Pat. No. 3,375,228 to Holoch et al.; U.S. Pat. No. 4,148,843 to Goossens; U.S. Pat. Nos. 4,562,243, 4,663,402, 4,665,137, and 5,091,480 to Percec et al.; U.S. Pat. Nos. 5,071,922, 5,079,268, 5,304,600, and 5,310,820 to Nelissen et al.; U.S. Pat. No. 5,338,796 to Vianello et al.; and European Patent No. 261,574 B1 to Peters et al.
in a preferred embodiment, the capped poly(arylene ether) may be prepared by reaction of an uncapped poly(arylene ether) with an anhydride in an alkenyl aromatic monomer as solvent. This approach has the advantage of generating the capped poly (arylene ether) in a form that can be immediately blended with other components to form a curable composition; using this method, no isolation of the capped poly (arylene ether) or removal of unwanted solvents or reagents is required.
A capping catalyst may be employed in the reaction of an uncapped poly(arylene ether) with an anhydride. Examples of such compounds include those known to the art that are capable of catalyzing condensation of phenols with the capping agents described above. Useful materials are basic compounds including, for example, basic compound hydroxide salts such as sodium hydroxide, potassium hydroxide, tetraalkylammonium hydroxides, and the like; tertiary alkylamines such as tributyl amine, triethylamine, dimethylbenzylamine, dimethylbutylamine and the like; tertiary mixed alkyl-arylamines and substituted derivatives thereof such as N,N-dimethylaniline; heterocyclic amines such as imidazoles, pyridines, and substituted derivatives thereof such as 2-methylimidazole, 2-vinylimidazole, 4-(dimethylamino)pyridine, 4-(1-pyrrolino)pyridine, 4-(1-piperidino)pyridine, 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, and the like. Also useful are organometallic salts such as, for example, tin and zinc salts known to catalyze the condensation of, for example, isocyanates or cyanate esters with phenols. The organometallic salts useful in this regard are known to the art in numerous publications and patents well known to those skilled in this art.
The composition may comprise a blend of at least two capped poly(arylene ethers). Such blends may be prepared from individually prepared and isolated capped poly(arylene ethers). Alternatively, such blends may be prepared by reacting a single poly(arylene ether) with at least two capping agents.
The composition may comprise the capped poly(arylene ether) in an amount of at least about 1 part, preferably at least about 10 parts, more preferably at least about 15 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer. The composition may comprise the capped poly (arylene ether) in an amount of up to about 70 parts, preferably up to about 50 parts, more preferably up to about 40 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer.
The composition further comprises an alkenyl aromatic monomer. The alkenyl aromatic monomer may have the structure 
wherein each R16 is independently hydrogen, C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C6-C18 aryl, or the like; each R17 is independently halogen, C1-C12 alkyl, C1-C12 alkoxyl, C6-C18 aryl, or the like; p is 1 to 4; and q is 0 to 5. When p=1, the alkenyl aromatic monomer is termed a monofunctional alkenyl aromatic monomer; when p=2-4, the alkenyl aromatic monomer is termed a polyfunctional alkenyl aromatic monomer. Suitable alkenyl aromatic monomers include styrene, alpha-methylstyrene, alpha-ethylstyrene, alpha-isopropylstyrene, alpha-tertiary-butylstyrene, alpha-phenylstyrene, and the like; halogenated styrenes such as chlorostyrene, dichlorostyrene, trichlorostyrene, bromostyrene, dibromostyrene, tribromostyrene, fluorostyrene, difluorostyrene, trifluorostyrene, tetrafluorostyrene, pentafluorostyrene, and the like; halogenated alkylstyrenes such as chloromethylstyrene, and the like; alkoxystyrenes such as methoxystyrene, ethoxystyrene, and the like; polyfunctional alkenyl aromatic monomers such as 1,3-divinylbenzene, 1,4-divinylbenzene, trivinylbenzene, 1,3-diisopropenylbenzene, 1,4-diisopropenylbenzene, and the like; and mixtures comprising at least one of the foregoing alkenyl aromatic monomers. In the foregoing substituted styrenes for which no substituent position is specified, the substituents may occupy any free position on the aromatic ring.
Preferred alkenyl aromatic monomers include styrene, alpha-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-t-butylstyrene, 3-t-butylstyrene, 4-t-butylstyrene, 1,3-divinylbenzene, 1,4-divinylbenzene, 1,3-diisopropenylbenzene, 1,4-diisopropenylbenzene, and the like, and mixtures comprising at least one of the foregoing alkenyl aromatic monomers. Preferred alkenyl aromatic monomers further include styrenes having from 1 to 5 halogen substituents on the aromatic ring, and mixtures comprising at least one such halogenated styrene.
The composition may comprise the alkenyl aromatic monomer in an amount of at least about 30 parts, preferably at least about 40 parts, more preferably at least about 50 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer. The composition may comprise the alkenyl aromatic monomer in an amount of up to about 98 parts, preferably up to about 80 parts, more preferably up to about 70 parts, per 100 parts total of the capped poly (arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer.
The composition further comprises an acryloyl monomer. The acryloyl monomer comprises at least one acryloyl moiety having the structure 
wherein R18 and R19 are each independently hydrogen, C1-C12 alkyl, or the like; and wherein R18 and R19 may be disposed either cis or trans about the carbon-carbon double bond. Preferably, R18 and R19 are each independently hydrogen or methyl. In one embodiment, the acryloyl monomer comprises at least two acryloyl moieties having the above structure and is termed a polyfunctional acryloyl monomer. In another embodiment, the acryloyl monomer comprises at least three acryloyl moieties having the above structure.
In one embodiment, the acryloyl monomer comprises at least one acryloyl moiety having the structure 
wherein R20-R22 are each independently hydrogen, C1-C12 alkyl, C2-C12 alkenyl, C6-C18 aryl, C7-C18 alkyl-substituted aryl, C7-C18 aryl-substituted alkyl, C2-C12 alkoxycarbonyl, C7-C18 aryloxycarbonyl, C8-C18 alkyl-substituted aryloxycarbonyl, C8-C18 aryl-substituted alkoxycarbonyl, nitrile, formyl, carboxylate, imidate, thiocarboxylate, or the like. Preferably, R20-R22 are each independently hydrogen or methyl. In one embodiment, the acryloyl monomer comprises at least two acryloyl moieties having the structure above. In another embodiment, the acryloyl monomer comprises at least three acryloyl moieties having the structure above.
Suitable acryloyl monomers include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, glycidyl (meth)acrylate, 2,2-dimethyl-3-hydroxypropyl-2,2-dimethyl-3-hydroxypropenoate, isobornyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, and the like; halogenated (meth)acrylates such as pentabromobenzyl (meth)acrylate, and the like; and acrylic or methacrylic amides such (meth)acrylamide, diacetone (meth)acrylamide, N(2-hydroxyethyl) (meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylamide, and the like; and mixtures comprising at least one of the foregoing acryloyl monomers. It will be understood that the suffix (meth)acryl-denotes either acryl- or methacryl-.
Suitable acryloyl monomers may further include vinyl functionalized anhydrides such as maleic anhydride; and epoxy acrylates, such as Epoxy Acrylate such as the Epoxy Acrylate sold by Sartomer Company under the trade names CN 120 AC16 and CN 118, Epoxidized Soy Bean Oil Acrylate CN 111, Epoxy Acrylate CN 104, Epoxy Acrylate CN 120, Low Viscosity Epoxy Acrylate CN 121, Epoxy Acrylate CN 124, Modified Epoxy Acrylate CN 136, Modified Epoxy Acrylate CN 115, Modified Epoxy Acrylate CN 116, Modified Epoxy Acrylate CN 117, Modified Epoxy Acrylate CN 119, Amine Modified Epoxy Acrylate CN 2100, Fatty Acid Modified Epoxy Acrylate CN 2101, Epoxy Acrylate CN 104 B80, Epoxy Acrylate CN 120 B60, Epoxy Acrylate CN 120 B80, Epoxy Acrylate CN 120 M50, Epoxy Acrylate CN 104 A80, Epoxy Acrylate CN 120 A60, Epoxy Acrylate CN 120 A75, Epoxy Acrylate CN 120 C60, Epoxy Acrylate CN 120 C80, Epoxy Acrylate CN 120 E50, Epoxy Acrylate CN 120 D80, Epoxy Acrylate with Styrene CN 120 S80, Epoxy Novolac Acrylate CN 112 C60, Epoxy Methacrylate CN 151, and the like.
Suitable acryloyl monomers may further include (meth)acrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, and the like; monoesters between a polyether polyol (e.g., polyethylene glycol, polypropylene glycol or polybutylene glycol) and an unsaturated carboxylic acid (e.g., (meth)acrylic acid); monoethers between a polyether polyol (e.g., polyethylene glycol, polypropylene glycol or polybutylene glycol) and a hydroxyl group-containing unsaturated monomer (e.g., 2-hydroxyethyl (meth)acrylate); adducts between an alpha,beta-unsaturated carboxylic acid and a monoepoxy compound (e.g., CARDURA(copyright) 10 from Shell Japan Ltd.) or an alpha-olefin epoxide; adducts between glycidyl (meth)acrylate and a monobasic acid (e.g., acetic acid, propionic acid, p-t-butylbenzoic acid, or a fatty acid); monoesters or diesters between an acid anhydride group-containing unsaturated compound (e.g., maleic anhydride or itaconic anhydride) and a glycol (e.g., ethylene glycol, 1,6-hexanediol or neopentyl glycol); hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, and the like; chlorine- and hydroxyl group-containing monomers such as 3-chloro-2-hydroxypropyl (meth)acrylate, and the like; C2-18 alkoxyalkyl esters of (meth)acrylic acid, such as methoxybutyl (meth)acrylate, ethoxybutyl (meth)acrylate, and the like; hydrocarbon ring-containing acrylate monomers such as phenyl (meth)acrylate, phenylethyl (meth)acrylate, phenylpropyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-acryloyloxyethyl hydrogenphthalate, 2-acryloyloxypropyl hydrogenphthalate, 2-acryloyloxypropyl hexahydrogenphthalate, 2-acryloyloxypropyl tetrahydrogenphthalate, an ester between p-t-butylbenzoic acid and hydroxyethyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and the like; and mixtures comprising at least one of the foregoing acryloyl monomers.
Other suitable acryloyl monomers include, for example, alkoxylated nonyl phenol acrylate, alkoxylated tetrahydrofurfuryl acrylate, allyl methacrylate, caprolactone acrylate, 2-(2-ethoxyethoxy)ethyl acrylate, (ethoxylated)2 hydroxyethyl methacrylate, (ethoxylated)5 hydroxyethyl methacrylate, (ethoxylated)10 hydroxyethyl methacrylate, (ethoxylated)4 nonyl phenol acrylate, (ethoxylated)4 nonyl phenol methacrylate, glycidyl methacrylate, isobornyl acrylate, isobornyl methacrylate, isodecyl acrylate, isodecyl methacrylate, isooctyl acrylate, lauryl acrylate, lauryl methacrylate, methoxy polyethylene glycol (number average molecular weight, Mn, of PEG portion=350 g/mol) monomethacrylate, methoxy polyethylene glycol (Mn of PEG portion=550 g/mol) monomethacrylate, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, polypropylene glycol monomethacrylate, propoxylated 2-allyl methacrylate, stearyl acrylate, stearyl methacrylate, tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate, tridecyl acrylate, tridecyl methacrylate, and the like; and mixtures comprising at least one of the foregoing acryloyl monomers.
Suitable acryloyl monomers may further include, for example, unsaturated polyester resins that are the polycondensation reaction product of one or more dihydric alcohols and one or more ethylenically unsaturated polycarboxylic acids. By polycarboxylic acid is meant polycarboxylic or dicarboxylic acids or anhydrides, polycarboxylic or dicarboxylic acid halides, and polycarboxylic or dicarboxylic esters. For example, suitable unsaturated polycarboxylic acids, and the corresponding anhydrides and the acid halides that contain polymerizable carbon-to-carbon double bonds, may include maleic anhydride, maleic acid, and fumaric acid. A minor proportion of the unsaturated acid, up to about forty mole percent, may be replaced by dicarboxylic or polycarboxylic acid that does not contain a polymerizable carbon-to-carbon bond. Examples thereof include the acids (and corresponding anhydrides and acid halides): orthophthalic, isophthalic, terephthalic, succinic, adipic, sebasic, methylsuccinic, and the like. Dihydric alcohols that are useful in preparing the polyesters include, for example, 1,2-propane diol (hereinafter referred to as propylene glycol), dipropylene glycol, diethylene glycol, 1,3-butanediol, ethylene glycol, glycerol, and the like. Examples of suitable unsaturated polyesters are the polycondensation products of (1) propylene glycol and maleic and/or fumaric acids; (2) 1,3-butanediol and maleic and/or fumaric acids; (3) combinations of ethylene and propylene glycols (approximately 50 mole percent or less of ethylene glycol) and maleic and/or fumaric acids; (4) propylene glycol, maleic and/or fumaric acids and dicyclopentadiene reacted with water; and the like; and mixtures comprising at least one of the foregoing acryloyl monomers. In addition to the above described polyesters, dicyclopentadiene modified unsaturated polyester resins such as those described in U.S. Pat. No. 3,883,612 to Pratt et al. may be used. The molecular weight of the polymerizable unsaturated polyester may vary over a considerable range, but ordinarily useful polyesters have a number average molecular weight of about 300 AMU to about 5,000 AMU, and more preferably about 500 AMU to about 5,000 AMU.
In a preferred embodiment, the acryloyl monomer may include compounds having greater than one acrylate moiety per molecule. Illustrative examples include compounds produced by condensation of an acrylic or methacrylic acid with a di-epoxide, such as bisphenol-A diglycidyl ether, butanediol diglycidyl ether, or neopenylene glycol dimethacrylate. Specific examples include 1,4-butanediol diglycidylether di(meth)acrylate, bisphenol A diglycidylether dimethacrylate, and neopentylglycol diglycidylether di(meth)acrylate, and the like. Also included as acryloyl monomers are the condensation of reactive acrylate or methacrylate compounds with alcohols or amines to produce the resulting polyfunctional acrylates or polyfunctional acrylamides. Examples include N,N-bis(2-hydroxyethyl)(meth)acrylamide, methylenebis((meth)acrylamide), 1,6-hexamethylenebis((meth)acrylamide), diethylenetriamine tris((meth)acrylamide), bis(gamma-((meth)acrylamide)propoxy)ethane, beta-((meth)acrylamide)ethylacrylate, ethylene glycol di((meth)acrylate)), diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylateglycerol di (meth)acrylate, glycerol tri(meth)acrylate, 1,3-propylene glycol di(meth)acrylate, dipropyleneglycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,2,4-butanetriol tri(meth)acrylate, 1,6-hexanedioldi(meth)acrylate, 1,4-cyclohexanediol di(meth)acrylate, 1,4-benzenediol di(meth)acrylate, pentaerythritoltetra(meth)acrylate, 1,5-pentanediol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate), 1,3,5-triacryloylhexahydro-1,3,5-triazine, 2,2-bis(4-(2-(meth)acryloxyethoxy)phenyl)propane, 2,2-bis(4-(2-(meth)acryloxyethoxy)-3,5-dibromophenyl)propane, 2,2-bis((4-(meth)acryloxy)phenyl)propane, 2,2-bis((4-(meth)acryloxy)-3,5-dibromophenyl)propane, and the like, and mixtures comprising at least one of the foregoing acryloyl monomers.
In addition to the acryloyl monomers described above, the acryloyl monomers may include alkoxylated difunctional monomers, such as alkoxylated diacrylate (sold as CD 802 by Sartomer Co.), alkoxylated aliphatic diacrylate, alkoxylated cyclohexane dimethanol diacrylate, alkoxylated cyclohexane dimethanol diacrylate, alkoxylated cyclohexane dimethanol diacrylate, alkoxylated hexane diol diacrylate, alkoxylated hexane diol diacrylate, alkoxylated hexane diol diacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,3-butylene glycol diacrylate, 1,3-butylene glycol dimethacrylate, cyclohexane dimethanol diacrylate, cyclohexane dimethanol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, dipropylene glycol diacrylate, (ethoxylated)3 bisphenol A diacrylate (it will be understood that the number following the ethoxylated term refers to the average number of ethoxy groups in the ethoxylate chains attached to each oxygen of bisphenol A), (ethoxylated)4 bisphenol A diacrylate, (ethoxylated)10 bisphenol A diacrylate, (ethoxylated)30 bisphenol A diacrylate, (ethoxylated)2 bisphenol A dimethacrylate, (ethoxylated)4 bisphenol A dimethacrylate, (ethoxylated)6 bisphenol A diacrylate, (ethoxylated)8 bisphenol A diacrylate, (ethoxylated)10 bisphenol A dimethacrylate, (ethoxylated)30 bisphenol A dimethacrylate, ethylene glycol dimethacrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol (Mn=200-600) di(meth)acrylate, tetraethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and the like; alkoxylated trifunctional monomers such as highly (propoxylated)5.5 glyceryl tri(meth)acrylate, (ethoxylated)3 trimethylolpropane tri(meth)acrylate, (ethoxylated)6 trimethylolpropane tri(meth)acrylate, (ethoxylated)15 trimethylolpropane tri(meth)acrylate, (ethoxylated)9 trimethylolpropane tri(meth)acrylate, (ethoxylated)20 trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, (propoxylated)3 glyceryl tri(meth)acrylate, (propoxylated)3 trimethylolpropane tri(meth)acrylate, (propoxylated)6 trimethylolpropane tri(meth)acrylate, tris (2-hydroxyethyl)isocyanurate tri(meth)acrylate solid, tris (2-hydroxyethyl) isocyanurate tri(meth)acrylate liquid, and the like; and tetrafunctional and pentafunctional monomers such as dipentaerythritol penta(meth)acrylate, di-(trimethylolpropane) tetra(meth)acrylate, (ethoxylated)4 pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate ester, pentaerythritol tetra(meth)acrylate, and the like; and mixtures comprising at least one of the foregoing acryloyl monomers.
Suitable acryloyl monomers may further include trifunctional urethane (meth)acrylates, such as the trifunctional urethane (meth)acrylates sold by Sartomer Company under the product names CN 929, CN 945 A60, CN 945 B85, CN 959, CN 962, CN 964, CN 965, CN 968, CN 980, CN 981, CN 983, CN 984, CN 944 B85, CN 953 B70, CN 963 B80, CN 964B85, CN 966 B85, CN 981 B88, CN 982 B88, CN 983 B88, CN 985 B88, CN 961 H81, CN 966 H90, CN 982 P90, CN 963 A80, CN 964 A 85, CN 965 A80, CN 966 A80, CN 981 A75, CN 982 A75, CN 980 M50, CN 961 E75, CN 963 E75, CN 963 E80, CN 964 E75, CN 982 E75, CN 963 J85, CN 966 J75, CN 966 I80, CN 966 R60, and CN 964 H90; hexafunctional urethane (meth)acrylates, such as the hexafunctional urethane (meth)acrylates sold by Sartomer Company under the product name CN 975; and urethane (meth)acrylates such as the urethane (meth)acrylates sold by Sartomer Company under the product names CN 972, CN 2901, CN 2902, CN 978, CN 999, CN 970 H75, CN 973 H85, CN 970 A60, CN 971 A80, CN 973 A80, CN 977 C70, CN 970 E60, CN 973 J75, and CN 1963; and the like; and mixtures comprising at least one of the foregoing acryloyl monomers.
Suitable acryloyl monomer may further include low viscosity oligomers, such as the low viscosity oligomers sold by Sartomer Company under the product numbers CN 130, CN 131, CN 135, and CN 137; polyester acrylate oligomers, such as the polyester acrylate oligomers sold by Sartomer Company under the product names Polyester Acrylate CN 293, CN 292, and CN 2200, and Chlorinated Polyester Acrylate CN 2201; adhesion promoting oligomers, such as the adhesion promoting oligomers sold by Sartomer Company under the product number CN 704; polybutadiene dimethacrylates, such as the polybutadiene dimethacrylates sold by Sartomer Company under the product numbers CN 301 and CN 303; Polybutadiene Urethane Diacrylate CN 302, and Polybutadiene Dimethacrylate CN 303; specialty oligomers, such as the specialty oligomers sold by Sartomer Company under the tradename SARBOX(copyright) as, for example, Aromatic Acid Methacrylate Half Ester in EEP Ester Solvent SB 401, SB 404, and SB 405, Aromatic Acid Methacrylate Half Ester in PM, Alcohol/EEP Ester Solvent SB 402, Aromatic Acid Methacrylate Half Ester in PM, Alcohol Solvent SB 400, Aromatic Acid Acrylate Half Ester in SR 339 SB 520 M35, Aromatic Acid Acrylate Half Ester in SR454 SB 520 E35, Aromatic Acid Methacrylate Half Ester in SR306 SB 520 A20, Aromatic Acid Methacrylate Half Ester in SR344 SB 500 K60, Aromatic Acid Methacrylate Half Ester in SR454 SB 500 E50, and Aromatic Acid Methacrylate Half Ester in SR454 SB 510 E35; acrylates, including, Low Viscosity Triacrylate Oligomer CN 132, Low Viscosity Triacrylate Oligomer CN 133, Low Viscosity Monoacrylate Oligomer CN 152, Urethane Acrylate CN 959, Polyester Acrylate CN 293, Urethane Acrylate CN 968, Urethane Acrylate CN 2901, Urethane Acrylate CN 2902, Urethane Acrylate CN 999, Low Viscosity Aliphatic Monoacrylate CN 135, Low Viscosity Aliphatic Monoacrylate CN 137, Amine Modified Epoxy Acrylate CN 2100, Fatty Acid Modified Epoxy Acylate CN 2101, Polyester Acrylate CN 2200, Chlorinated Polyester Acrylate CN 2201, Acrylated Acrylic CN 2800, Epoxy Acrylate CN 120 AC16, Polybutadiene Urethane Diacrylate CN 302, Polybutadiene Dimethacrylate CN 303, (Meth)Acrylate Functional Monomer P-Cure 300, and (Meth)Acrylate Functional Monomer P-Cure 301; functional acrylic oligomers, such as the functional acrylic oligomers sold by Sartomer Company under the tradename SARCRYL(copyright) as SARCRYL(copyright) Functional AcrylicSarcryl CN816, SARCRYL(copyright) Functional AcrylicSarcryl CN817, SARCRYL(copyright) Functional AcrylicSarcryl CN818, Amine Modified Polyether Acrylate CN 501, Amine Modified Polyether Acrylate CN 502, Amine Modified Polyether Acrylate CN 550, Amine Modified Polyether Acrylate CN 551, Alkoxylated Trifunctional Acrylate Ester such as SR 9008 sold by Sartomer Co., Metallic Diacrylate SR 9016, and metallic diacrylates such as zinc diacrylate, lithium diacrylate, sodium diacrylate, magnesium diacrylate, calcium diacrylate, aluminum diacrylate, Monofunctional Acid Ester CD 9050, Trifunctional Acid Ester CD 9051 and CD 9052, Trifunctional Acrylate Ester SR 9012, and Trifunctional Methacrylate Ester SR 9009 and SR 9011; and the like; and mixtures comprising at least one of the foregoing acryloyl monomers.
Highly preferred acryloyl monomers include trimethylolpropane tri(meth)acrylate, 1,6-hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, propylene glycol di (meth)acrylate, cyclohexanedimethanol di(meth)acrylate, butanedioldi(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, isobornyl(meth)acrylate, cyclohexyl (meth)acrylate, butyl(meth)acrylate, methyl (meth)acrylate, dibutyl fumarate, dibutyl maleate, glycidyl (meth)acrylate, ethyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, hexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, decyl (meth)acrylate, octyl (meth)acrylate, and the like, and mixtures comprising at least one of the foregoing acryloyl monomers.
In a preferred embodiment, the acryloyl monomer comprises an acryloyl monomer having a number average molecular weight less than about 1,000 AMU and an acryloyl monomer having a number average molecular weight greater than about 2,500 AMU; more preferably the acryloyl monomer comprises an acryloyl monomer having a number average molecular weight less than about 500 AMU and an acryloyl monomer having a number average molecular weight greater than about 3,000 AMU.
The composition may comprise the acryloyl monomer in an amount of at least about 1 part, preferably at least about 5 parts, more preferably at least about 15 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer. The composition may comprise the acryloyl monomer in an amount up to about 69 parts, preferably up to about 50 parts, more preferably up to 30 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer.
The composition may, optionally, further comprise a multivalent metal ion. Suitable multivalent metal ions include those in Groups IIA, IIIA, and IB-VIIIB of the periodic table. Preferred multivalent ions include ions of magnesium, calcium, zinc, and aluminum. The multivalent metal ions may be present, for example, as salts with counterions including halides, hydroxides, oxides, and the like. When present, the multivalent metal ion may be used in an amount of about 0.1 parts by weight to about 5 parts by weight per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer, where parts by weight of the multivalent metal ion are based on the elemental metal. Within this range, it may be preferred to use the multivalent metal ion in an amount of at least about 0.2 parts by weight, more preferably at least about 0.3 parts by weight, of the multivalent metal ion. Also within this range, it may be preferred to use up to about 3 parts by weight, more preferably up to about 2.5 parts by weight, of the multivalent metal ion.
The composition may, optionally, further comprise a curing catalyst to increase the curing rate of the unsaturated components. Curing catalysts, also referred to as initiators, are well known to the art and used to initiate the polymerization, cure or crosslink any of numerous thermoplastics and thermosets including unsaturated polyester, vinyl ester and allylic thermosets. Non-limiting examples of curing catalysts are those described in xe2x80x9cPlastic Additives Handbook, 5th Editionxe2x80x9d Hans Zweifel, Ed, Carl Hanser Verlag Publishers, Munich, 2001., and in U.S. Pat. No. 5,407,972 to Smith et al., and U.S. Pat. No. 5,218,030 to Katayose et al. The curing catalyst for the unsaturated portion of the thermoset may include any compound capable of producing radicals at elevated temperatures. Such curing catalysts may include both peroxy and non-peroxy based radical initiators. Examples of useful peroxy initiators include, for example, benzoyl peroxide, dicumyl peroxide, methyl ethyl ketone peroxide, lauryl peroxide, cyclohexanone peroxide, t-butyl hydroperoxide, t-butyl benzene hydroperoxide, t-butyl peroctoate, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)-hex-3-yne, di-t-butylperoxide, t-butylcumyl peroxide, alpha,alphaxe2x80x2-bis (t-butylperoxy-m-isopropyl)benzene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, dicumylperoxide, di(t-butylperoxy isophthalate, t-butylperoxybenzoate, 2,2-bis(t-butylperoxy)butane, 2,2-bis(t-butylperoxy)octane, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, di(trimethylsilyl)peroxide, trimethylsilylphenyltriphenylsilyl peroxide, and the like, and mixtures comprising at least one of the foregoing curing catalysts. Typical non-peroxy initiators include, for example, 2,3-dimethyl-2,3-diphenylbutane, 2,3-trimethylsilyloxy-2,3-diphenylbutane, and the like, and mixtures comprising at least one of the foregoing curing catalysts.
In a preferred embodiment, the curing catalyst may comprise t-butyl peroxybenzoate or methyl ethyl ketone peroxide. The curing catalyst may promote curing at a temperature of about 0xc2x0 C. to about 200xc2x0 C.
When present, the curing catalyst may be used in an amount of at least about 0.1 part, preferably at least about 1 part, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer. The curing catalyst may be used in an amount of up to about 10 parts, preferably up to about 5 parts, more preferably up to about 3 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer.
The composition may, optionally, further comprise a curing promoter to decrease the gel time. Suitable curing promoters include transition metal salts and complexes such as cobalt naphthanate; and organic bases such as N,N-dimethylaniline (DMA) and N,N-diethylaniline (DEA). Preferably, cobalt naphthanate and DMA are used in combination. When present, the promoter may be used in an amount of about 0.05 to about 3 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer.
When the composition is to be cured using ultraviolet light, it may further comprise a photoinitiator, such as, for example, the photoinitiators described in U.S. Pat. No. 5,407,972, including, for example, ethyl benzoin ether, isopropyl benzoin ether, butyl benzoin ether, isobutyl benzoin ether, alpha,alpha-diethoxyacetophenone, alpha,alpha-dimethoxy-alpha-phenylacetophenone, diethoxyphenylacetophenone, 4,4xe2x80x2-dicarboethoxybenzoin ethylether, benzoin phenyl ether, alpha-methylbenzoin ethyl ether alpha-methylolbenzoin methyl ether, trichloroacetophenone, and the like, and mixtures comprising at least one of the foregoing photoinitiators.
In addition to the components described above, the composition may optionally comprise an uncapped poly(arylene ether) in an amount that does not detract from the desirable properties of the composition. Such amounts can be readily determined without undue experimentation. High molecular weight uncapped poly(arylene ether)s, for example those having intrinsic viscosities of at least about 0.3 dl/g, may be preferred for this purpose.
The composition may further comprise additives known in the art, including, for example, flame retardants; lubricants including mold release agents; antioxidants; thermal stabilizers; ultraviolet stabilizers; pigments, dyes, and colorants; anti-static agents; fillers including fibrous fillers, and polymeric fillers; conductive agents; blowing agents; and the like; and combinations comprising at least one of the foregoing additives. Such additives are described in detail in xe2x80x9cPlastic Additives Handbook, 5th Editionxe2x80x9d Hans Zweifel, Ed, Carl Hanser Verlag Publishers, Munich, 2001.
Flame retardants include, for example, brominated flame retardant compounds. Preferred brominated flame retardant compounds include, for example, brominated diphenyl ethers varying in bromination levels from 2-10 bromines per molecule such as, for example, tetrabromodiphenyloxide, pentabromodiphenyloxide, octabromodiphenyloxide, and decabromodiphenyl oxide. Other brominated derivatives include tetradecabromodiphenoxybenzene, tetrabromocyclooctane, 2,4,6-tribromophenylmaleimide, phenyl-1,2,3,4-tetrabromophthalamide, 2,4,6-tribromophenyl-1,2,3,4-tetrabromophthalimide, 1,4-phenylene-bis(1,2,3,4-tetrabromophthalimide), 1,3-phenylene-bis(1,2,3,4-tetrabromophthalimide, hexabromocyclododecane, 4-bromophenyl(1,2,3,4-tetrabromotetrabromophtalamide), pentabromobenzylacrylate, 1,6-bis(1,2,3,4-tetrabromophthalmido)hexane, 1,2-bis(1,2,3,4-tetrabromophthalmido)ethane, dibromoethyl dibromocyclohexane, hexabromocyclododecane, tetrabromobisphenol-A, bis(2,3-dibromopropyl ether), tetrabromophthalic anhydride, Diels Alder adducts of chlorinated cyclopentadienes and diene derivatives such as cyclooctadiene, dechlorane, 1,3,5-tris(2,4,6-tribromophenoxy)triazine, polybrominated diphenyl ethers, poly(2,6-dibromophenylene ether), brominated styrene monomers such as dibromostyrene, brominated polycarbonate, bis(tribromophenoxy)ethane, perbrominatedbibenzyl, dibromoethylcyclohexane, decabromodiphenyl oxide brominated polystyrene, brominated cyclododecane, tetrabromobisphenol-A diglycidyl ether and oligomers thereof, bis(2-hydroxyethyl ether) of tetrabromobisphenol-A, bis(2-methacroyloxyethyl ether) of tetrabromobisphenol-A, dibromoneopentylglycol dimethacrylate, and the like, and combinations comprising at least one of the foregoing brominated derivatives. Preferred phosphorus-containing flame retardants include, for example, C6-C100 aromatic, C6-C100 aliphatic, or C6-C100 mixed aromatic-aliphatic phosphate esters such as, for example, triphenyl phosphate, tricresyl phosphate, triethyl phosphate, dimethyl methylphosphonate and aluminum and zinc salts thereof, tris(2-allylphenyl)phosphate, isopropylphenyl diphenylphosphate, tris(2-methoxy-4-allylphenyl)phosphate, tris(2-propenylphenyl) phosphate, tris(4-vinylphenyl)phosphate, bis(diphenylphosphate ester)s of bisphenols including bisphenol-A and resorcinol and hydroquinone, bis(diphenyl phosphoramide) s of diamines such as 1,6-hexanediamine and piperidine, and alkylated or substituted derivatives thereof. Other suitable flame retardants include melamine, cyclophosphazenes such as hexaamino and hexaphenyl cyclophosphazenes and derivatives thereof, aluminum trihydrate, zinc borate, borax, tin oxide, zinc hydroxy stannate, zinc stannate, magnesium hydroxide, and hydromagnesite, huntite, molybdenum trioxide, zinc molybdate, calcium molybdate, ammonium molybdate, ferrous oxides, ferrocene, trischloroethylphosphate, dialkyl vinylphosphonates such as diethylvinylphosphonate, ammonium polyphosphate, melamine phosphonates, urea, red phosphorus, phosphorylated polyvinyl alcohol, and the like. If brominated flame retardants are used, it is preferred that the bromine content of the brominated flame retardant be greater than 30 weight percent, more preferably greater than 60 weight percent of the total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer. The high bromine content of the flame retardant allows one to obtain UL-94 flammability and at the same time maintain high poly(arylene ether) content and optimal dielectric properties.
Synergists such as ferrous oxide, antimony oxide, and the like may be added to improve the flame retardancy of the desired composition.
Lubricants may include fatty alcohols and their dicarboxylic acid esters including cetyl, stearyl and tall oil alcohol, distearyl adipate, distearyl phthalate, fatty acid esters of glycerol and other short chain alcohols including glycerol monooleate, glycerol monostearate, glycerol 12-hydroxystearate, glycerol tristearate, trimethylol propane tristearate, pentaerythritol tetrastearate, butyl stearate, isobutyl stearate, stearic acids, 12-hydroxystearic acid, oleic acid amide, erucamide, bis(stearoyl)ethylene diamine, calcium stearate, zinc stearate, neutral lead stearate, dibasic lead stearate, stearic acid complex esters, oleic acid complex esters, calcium soap containing complex esters, fatty alcohol fatty acid esters including isotridecyl stearate, cetyl palmitate, stearyl stearate, behenyl behenate, montanic acid, montanic acid ethylene glycol esters, montanic acid glycerol esters, montanic acid pentaerythritol esters, calcium soap containing montanic acid esters, calcium montanate, sodium montanate; linear or branched polyethylene, partially saponified polyethylene wax, ethylene-vinyl acetate copolymer, crystalline polyethylene wax; natural or synthetic paraffin including fully refined wax, hardened paraffin wax, synthetic paraffin wax, microwax, and liquid paraffin; fluoropolymers including polytetrafluoroethylene wax, and copolymers with vinylidene fluoride.
The composition may further comprise one or more fillers, including low-aspect ratio fillers, fibrous fillers, and polymeric fillers. Examples of such fillers well known to the art include those described in xe2x80x9cPlastic Additives Handbook, 5th Editionxe2x80x9d Hans Zweifel, Ed, Carl Hanser Verlag Publishers, Munich, 2001. Non-limiting examples of fillers include silica powder, such as fused silica and crystalline silica; boron-nitride powder and boron-silicate powders for obtaining cured products having low dielectric constant and low dielectric loss tangent; the above-mentioned powder as well as alumina, and magnesium oxide (or magnesia) for high temperature conductivity; and fillers, such as wollastonite including surface-treated wollastonite, calcium sulfate (as its anhydride, dihydrate or trihydrate), calcium carbonate including chalk, limestone, marble and synthetic, precipitated calcium carbonates, generally in the form of a ground particulate which often comprises 98+% CaCO3 with the remainder being other inorganics such as magnesium carbonate, iron oxide, and alumino-silicates; surface-treated calcium carbonates; talc, including fibrous, modular, needle shaped, and lamellar talc; glass spheres, both hollow and solid, and surface-treated glass spheres typically having coupling agents such as silane coupling agents and/or containing a conductive coating; and kaolin, including hard, soft, calcined kaolin, and kaolin comprising various coatings known to the art to facilitate the dispersion in and compatibility with the thermoset resin; mica, including metallized mica and mica surface treated with aminosilanes or acryloylsilanes coatings to impart good physicals to compounded blends; feldspar and nepheline syenite; silicate spheres; flue dust; cenospheres; finite; aluminosilicate (armospheres), including silanized and metallized aluminosilicate; natural silica sand; quartz; quartzite; perlite; tripoli; diatomaceous earth; synthetic silica, including those with various silane coatings, and the like.
The above fillers may be used in metallized or silane coated forms to improve compatibility and adhesion with the thermoset blend.
Other mineral fillers include silicon carbide to increase the abrasive action of polymers; molybdenum sulfide to improve the lubricity, zinc sulfide to impart a white coloration; aluminum silicate (mullite), synthetic calcium silicate and zirconium silicate to improve slip properties; barium titanate to enhance dielectric properties; barium ferrite to produce magnetized polymers; and barium sulfate and heavy spar.
Other fillers include metals and metal oxides including particulate or fibrous aluminum, bronze, zinc, copper and nickel to improve, for example, thermal, electrical conductivity or resistance to neutron or gamma rays. Aluminum hydroxide may be incorporated to improve the flammability of a polymer resin.
Other fillers include carbon, such as carbon black for use as a potential colorant, and conductive carbon black to achieve improved volume conductivity and heat deflection temperature. Graphite, such as graphite powder may be used to impart lubricity and/or conductivity to the formulation.
Other fillers include flaked fillers and reinforcements such as glass flakes, flaked silicon carbide, aluminum diboride, aluminum flakes, and steel flakes.
Fibrous fillers include short inorganic fibers, including processed mineral fibers such as those derived from blends comprising at least one of aluminum silicates, aluminum oxides, magnesium oxides, and calcium sulfate hemihydrate.
Other fibrous fillers include natural fillers and reinforcements, such as wood flour obtained by pulverizing wood, and fibrous products such as cellulose, cotton, sisal, jute, starch, cork flour, lignin, ground nut shells, corn, rice grain husks.
Other fibrous fillers include synthetic reinforcing fibers, including polyesters such as polyethylene terephthalate, polyvinylalcohol; and high tenacity fibers with high thermal stability, including basalt fibers, carbon fibers, aromatic polyamide fibers, polybenzimidazole, polyimide fibers such as polyimide 2080 and PBZ fiber (both products of Dow Chemical Company, Midland, Mich. USA); and polyphenylene sulfide fiber, polyether ether ketone fibers, boron fibers, ceramic fibers such as silicon carbide, and fibers from mixed oxides of aluminum, boron and silicon sold under the trade name NEXTEL(copyright) by 3M Co., St. Paul, Minn. USA.
Also included among fibrous fillers are single crystal fibers or xe2x80x9cwhiskersxe2x80x9d including silicon carbide, alumina, boron carbide, carbon, iron, nickel, copper.
Also included among fibrous fillers are glass fibers, including textile glass fibers such as E, A, C, ECR, R, S, D, and NE glasses and quartz.
In addition, organic reinforcing fibrous fillers may be used in the present invention including, organic polymers capable of forming fibers. Illustrative examples of such organic fibrous fillers include, for example, poly(ether ketone), polyimide, polybenzoxazole, poly(phenylene sulfide), polyesters, polyethylene, aromatic polyamides, aromatic polyimides or polyetherimides, polytetrafluoroethylene, acrylic resins, and poly(vinyl alcohol). Also included are natural organic fibers known to those skilled in the art, including cotton, cloth, hemp cloth, felt, and natural cellulosic fabrics such as Kraft paper, cotton paper and glass fiber containing paper.
Such reinforcing fillers may be provided in the form of monofilament or multifilament fibers and can be used either alone or in combination with other types of fiber, through, for example, co-weaving or core/sheath, side-by-side, orange-type or matrix and fibril constructions, or by other methods known to one skilled in the art of fiber manufacture. Typical cowoven structures include glass fiber-carbon fiber, carbon fiber-aromatic polyimide (aramid) fiber, and aromatic polyimide fiber-glass fiber. Fibrous fillers may be supplied in the form of, for example, rovings, woven fibrous reinforcements, such as 0-90 degree fabrics, non-woven fibrous reinforcements such as continuous strand mat, chopped strand mat, tissues, papers and felts and 3-dimensionally woven reinforcements, performs and braids.
For most applications fibrous reinforcements preferred are selected from the group consisting of E, S, D, and NE glass fibers and quartz, polyethylene terephthalate, basalt fibers, carbon fibers, polyethylene fiber, aromatic polyamide fibers, polybenzimidazole fiber, polyimide fibers, polyphenylene sulfide fiber, polyether ether ketone fibers, boron fibers, and ceramic fibers such as silicon carbide.
Fibrous fillers may also include vapor-grown carbon fibers include those having an average diameter of about 3.5 to about 500 nanometers as described in, for example, U.S. Pat. Nos. 4,565,684 and 5,024,818 to Tibbetts et al.; U.S. Pat. No. 4,572,813 to Arakawa; U.S. Pat. Nos. 4,663,230 and 5,165,909 to Tennent; U.S. Pat. No. 4,816,289 to Komatsu et al.; U.S. Pat. No. 4,876,078 to Arakawa et al.; U.S. Pat. No. 5,589,152 to Tennent et al.; and U.S. Pat. No. 5,591,382 to Nahass et al.
Descriptions of various of fibrous fillers, their incorporation and utility may be found in Engineered Materials Handbook, Volume 1, Composites, ASM International Metals Park, Ohio, copyright 1987 Cyril A. Dostal Senior Ed.
When present, the fillers, including fibrous fillers, may be used in an amount of about 0.005 to about 1000 parts, preferably about 1 to about 500 parts, more preferably about 10 to about 250 parts, yet more preferably about 50 to about 200 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer.
These aforementioned fillers may be added to the thermosetting resin without any treatment, or after surface treatment, generally with an adhesion promoter.
The formulation may also contain adhesion promoters to improve adhesion of the thermosetting resin to the filler or to an external coating or substrate. Also possible is treatment of the aforementioned inorganic fillers with adhesion promoter to improve adhesion. Adhesion promoters include chromium complexes, silanes, titanates, zirco-aluminates, propylene maleic anhydride copolymers, reactive cellulose esters and the like. Chromium complexes include those sold by DuPont under the tradename VOLAN(copyright). Silanes include molecules having the general structure (RO)(4xe2x88x92n) SiYn wherein n=1-3, R is an alkyl or aryl group and Y is a reactive functional group which can enable formation of a bond with a polymer molecule. Particularly useful examples of coupling agents are those having the structure (RO)3 SiY. Typical examples include vinyl-triethoxysilane, vinyl tris(2-methoxy)silane, g-methacryloxypropyltrimethoxy silane, g-aminopropyltriethoxysilane, g-glycidoxypropyltrimethoxysilane, g-mercaptopropyltrimethoxysilane. Titanates include those developed by S. J. Monte et al. in Ann. Chem. Tech Conf. SPI (1980), Ann. Tech Conf. Reinforced Plastics and Composite inst. SPI 1979, Section 16E, New Orleans; and S. J. Monte, Mod. Plastics Int. 14(1984) 6 pg. 2. Zirco-aluminates include those described by L. B. Cohen in Plastics Engineering 39 (1983)11, pg. 29. The adhesion promoter may be included in the thermosetting resin itself, or coated onto any of the fillers described above to improve adhesion between the filler and the thermosetting resin. For example such promoters may be used to coat a silicate fiber or filler to improve adhesion of the resin matrix.
Polymeric fillers, including thermoplastics, rubbers, elastomers, and the like, may also be used. Examples of thermoplastics include powdery engineering resins, such as polycarbonate, thermoplastic polyester, polyestercarbonate, polyphenylene ether, polysulfone, polyether sulfone, and polyacrylate; powdery polyolefins, such as polyethylene, polypropylene and poly-4-methyl pentene-1; fluoroplastics, such as polytetrafluoroethylene, tetrafluoroethylene-propylene copolymer; chlorinated polyethylene; ethylene vinyl acetate copolymers; polyacrlyates such as polybutyl acrylate, poly(2-hexyl acrylate); core-shell impact modifiers, such as polymethyl methacrylate-polybutylacrylate, poly(acrylonitrile-butadiene-styrene), poly(styrene-acrylonitrile) copolymers, poly(methyl methacrylate-butadiene-styrene) terpolymers; polyphenylene ether; ethylene propylene rubbers including diene modified ethylene propylene rubbers, and butadiene/styrene block copolymers. Polymeric fillers may also include organic fillers such as rubbers, including acrylate-butadiene rubber, copolymers of ethyl acrylate (or other acrylates) and a small amount of a monomer that facilitates vulcanization (acrylic rubber), terpolymer from tetrafluoroethylene, trifluoronitrosomethane, and nitroso-perfluorobutyric acid (nitroso rubber), ethylacrylate-acrylonitrile copolymer (acrylate rubber), alkylene sulfide rubber, urethane rubber based on polyester, butadiene rubber (polybutadiene), bromobutyl rubber, chlorobutyl rubber, polychlorotrifluoroethylene (fluoro rubber), chloropolyethylene, epichlorohydrin homopolymer rubber (polychloromethyloxiran), chloroprene rubber (polychloroprene), chlorosulfonylpolyethylene, ethylene-ethyl acrylate copolymer (e.g., those sold by DuPont under the tradename VAMAC(copyright)), copolymer of ethylene oxide (oxiran) and chloromethyloxiran (epichlorohydrin rubber), epoxidized natural rubber, ethylene-propylene-diene terpolymer, ethylene-propylene copolymer, urethane rubber based on polyether, epichlorohydrin-ethyleneoxide terpolymer, ethylene-vinylacetate copolymer, methyl silicone rubber with fluoro groups, rubber having fluoro or fluoroalkyl or fluoroalkoxy substituent groups on the polymer chain, copolymer from propylene oxide and allyl glycidyl ether, hydrogenated nitrile rubber, isobutylene-isoprene rubber (butyl rubber), polyisobutene, synthetic isoprene rubber, liquid silicone rubber, methyl silicone rubber, and acrylonitrile-butadiene rubber. Polymeric fillers further include functionalized polybutadiene and polybutadiene-acrylonitrile rubbers including those sold under the tradename HYCAR(copyright) by B.F. Goodrich Company, including, carboxy functionalized polybutadiene rubbers such as HYCAR(copyright) 2000X162CTB (Carboxyl Equivalents=0.045; Mn=4,200; Carboxyl Equivalents per chain 1.9); HYCAR(copyright) CS 8596 (Carboxyl equivalents=0.032; Mn=6250; Carboxyl equivalents/chain=approx. 2), and carboxy terminated poly(butadiene-co-acrylonitrile) rubbers such as HYCAR(copyright) 1300X31 CTBN (Acrylonitrile content=10%; Carboxyl Equivalents=0.050; Mn=3,800; Carboxyl equivalents/chain=1.9); HYCAR(copyright) 1300X8 CTBN(Acrylonitrile content=18%; Carboxyl Equivalents=0.052; Mn=3,550; Carboxyl equivalents/chain=1.8) HYCAR(copyright) 1300X13 CTBN (Acrylonitrile content=26%; Carboxyl Equivalents=0.057; Mn=3,150; Carboxyl equivalents/chain=1.8); HYCAR(copyright)1300OX9CTBNX (Acrylonitrile content=18; Carboxyl Equivalents=0.067; Mn=3,600; Carboxyl equivalents/chain=2.4); HYCAR(copyright) 1300X18 CTBNX (Acrylonitrile content=21.5; Carboxyl Equivalents=0.070; Mn=3,400; Carboxyl equivalents/chain=2.4), vinyl and carboxy functionalized poly(butadiene-acrylonitrile) rubbers including HYCAR(copyright) 1300X33 VTBNX (Acrylonitrile content=18%; Carboxyl Equivalents per 100 rubber=0.009 maximum); HYCAR(copyright) 1300X43 VTBNX (Acrylonitrile content=21.5%; Carboxyl Equivalents per 100 rubber=0.009 maximum); epoxy terminated poly(butadiene-acrylonitrile) rubber HYCAR(copyright) 1300X40 ETBN (Carboxyl Equivalents per chain=0.027 maximum; 50% solution in styrene); amine terminated polybutadiene-acrylonitrile rubbers such as HYCAR(copyright) 1300X21ATBN (Acrylonitrile content=10%), 1300X16ATBN (Acrylonitrile content=18%); HYCAR(copyright) 1300X45 ATBN (Acrylonitrile content=18%); 1300X35ATBN (Acrylonitrile content=26%); HYCAR(copyright) 1300X42 ATBN (Acrylonitrile content=18%); also included are the functionalized polybutadienes and poly(butadiene-styrene) random copolymers sold by Ricon Resins, Inc. under the trade name RICON(copyright), RICACRYL(copyright), and RICOBOND(copyright) resins these include butadienes containing both low vinyl content such as RICON(copyright) 130, 131, 134, 142 polybutadienes containing high vinyl content such as RICON(copyright) 150, 152, 153, 154, 156, 157, and P30D; also random copolymers of styrene and butadiene including RICON(copyright) 100, 181, 184, and maleic anhydride grafted polybutadienes and the alcohol condensates derived therefrom such as RICON(copyright) 130MA8, RICON(copyright) MA13, RICON(copyright) 130MA20, RICON(copyright) 131MAS, RICON(copyright) 131MA10, RICON(copyright) MA17, RICON(copyright) MA20, RICON(copyright) 184MA6 and RICON(copyright) 156MA17; also include are polybutadienes which may be used to improve adhesion including RICOBOND(copyright) 1031, RICOBOND(copyright) 1731, RICOBOND(copyright) 2031, RICACRYL(copyright) 3500, RICOBOND(copyright) 1756, RICACRYL(copyright) 3500; also are included the polybutadienes RICON(copyright) 104 (25% polybutadiene in heptane), RICON(copyright) 257 (35% polybutadiene in styrene), and RICON(copyright) 257 (35% polybutadiene in styrene); also are included (meth)acrylic functionalized RICACRYL(copyright) 3100, RICACRYL(copyright) 3500, and RICACRYL(copyright) 3801. Also are included are powder dispersions of functional polybutadiene derivatives including, for example, RICON(copyright) 150D, 152D, 153D, 154D, P30D, RICOBOND(copyright) 0 1731 HS, and RICOBOND(copyright) 1756HS. Further butadiene resins include poly(butadiene-isoprene) block and random copolymers, such as those with molecular weights from 3,000-50,000 AMU and polybutadiene homopolymers having molecular weights from 3,000-50,000 AMU. Also included are polybutadiene, polyisoprene, and polybutadiene-isoprene copolymers functionalized with maleic anhydride functions, 2-hydroxyethylmaleic functions, or hydroxylated functionality. Polymeric fillers further include polyacrylonitrile-chloroprene, polyacrylonitrile-isoprene, polyisoprene, polyglycol ethers, such as polypropylene glycol, polyethylene glycol, polyethylene glycol-polypropylene glycol block and random copolymers, polytetrahydrofuran, polypropylene oxide-allylglycidyl ether copolymers, polyvinylpyridine-butadiene, polyethylene, and methyl silicone rubbers and fluids with vinyl or phenyl groups. Polymeric fillers may also include polyfluoralkoxyphosphazene, polynorbornene, polypropylene, vinylpyridine-styrene-butadiene rubber, polyurethanes, methyl silicones with phenyl and vinyl groups, polystyrene-butadiene, styrene-butadiene-styrene block copolymer (thermoplastic elastomer), styrene-chloroprene rubber, polysiloxane treated EPDM, styrene-isoprene rubber, styrene-isoprene-styrene block copolymer (thermoplastic elastomer), polythioglycol ether, polytetrafluoroethylene, polysulfide rubbers, trans-polyoctenamer, trans-polypentenamer, thermoplastic polyurethanes, crosslinkable polyethylene, poly(vinylchloride-co-vinyl acetate-co acrylic acid), poly(ethylene-co-vinylacetate-co-acrylic acid).
Also included among polymeric fillers are electrically conductive polymers such as polypyrrole, polyaniline, polyphenylene, polyacetylene, and substituted derivatives there of, including derivatives substituted with C1-C25 alkyl, C1-C25 alkoxy, C2-C25 alkylcarbonyl, C2-C25 alkylcarbonyloxy, C6-C25 aryl, C6-C25 aryloxy, C7-C25 arylcarbonyl, and C7-C25 arylcarbonyloxy.
When present, the polymeric fillers may be used in amounts of about 0.005 to about 200 parts, preferably about 2 to about 30 parts, more preferably about 5 to about 25 parts, yet more preferably about 10 to about 20 parts, per 100 parts total of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer. The polymeric filler may or may not be reactive with the uncured composition and may or may not be soluble in the uncured or cured composition to which it is added.
Additives may also include blowing agents such as azo compounds like diazoaminobenzene, azobisisobutyronitrile, azodicarbonamide, azodicarbonic acid, benzene sulfonyl hydrazide, benzene-1,3-disulfonylhydrazide, diphenyloxide-4,4xe2x80x2-disulfonylhydrazide, p-toluenesulfonic acid hydrazide, N,Nxe2x80x2-dinitrosopentamethylenetetraamine, N,N-dimethyl-N,Nxe2x80x2-dinitrosophthalamide, and sodium carbonate blends with acidic compounds such as tartaric acid, and the like.
In a preferred embodiment, the composition is substantially free of water, meaning that the composition comprises water in an amount less than about 1 weight percent, preferably less than about 0.5 weight percent, more preferably less than about 0.1 weight percent, based on the total weight of the composition.
The curable compositions may be dissolved in an effective amount of an inert organic solvent, typically to a solute content of about 30%-60% by weight. The identity of the solvent is not critical, provided that it may be removed by suitable means such as evaporation. Aromatic hydrocarbons, especially toluene, are preferred. The order of blending and dissolution also is not critical. However, in order to avoid premature curing, catalyst and hardener components generally should not be brought initially into contact with uncapped poly(arylene ether) and polymerizable monomer composition at a temperature above about 60xc2x0 C. Proportions of components herein do not include solvent unless otherwise indicated.
There is no particular limitation on the method by which the composition is prepared. The composition may be prepared by forming an intimate blend of the capped poly(arylene ether), the alkenyl aromatic monomer, and the acryloyl monomer. Alternatively, the composition may be prepared directly from an uncapped poly (arylene ether) by dissolving the uncapped poly(arylene ether) in a portion of the alkenyl aromatic monomer, adding a capping agent to form the capped poly(arylene ether) in the presence of the alkenyl aromatic monomer, and adding the acryloyl monomer, and any other components to form the thermoset composition. The composition may also be formed by dispersing particulate capped poly(arylene ether) in the other components, where the particulate (i.e., powder) preferably has a particle size of about 0.5 to about 300 micrometers.
There is no particular limitation on the method by which the composition may be cured. The composition may, for example, be cured thermally or by using irradiation techniques, including UV irradiation and electron beam irradiation. When heat curing is used, the temperature selected may be about 80xc2x0 C. to about 300xc2x0 C., and preferably about 120xc2x0 C. to about 240xc2x0 C. The heating period may be about 1 minute to about 10 hours, though such heating period may advantageously be about 1 minute to about 6 hours, more preferably about 3 hours to about 5 hours. Such curing may be staged to produce a partially cured and often tack-free resin, which then is fully cured by heating for longer periods or temperatures within the aforementioned ranges.
The cured composition may preferably exhibit a glass transition temperature of at least about 100xc2x0 C., more preferably 120xc2x0 C., yet more preferably at least about 130xc2x0 C., still more preferably at least about 140xc2x0 C.
The cured composition may preferably exhibit a coefficient of thermal expansion (CTE) below its glass transition temperature of not greater than about 30 micrometer/meter-xc2x0 C. (xcexcm/m-xc2x0 C.), preferably not greater than about 25 xcexcm/m-xc2x0 C., more preferably not greater than about 20 xcexcm/m-xc2x0 C.
Processes useful for processing the composition include those generally known to the art for the processing of thermosetting resins. Such processes have been described in the literature as in, for example, Engineered Materials Handbook, Volume 1, Composites, ASM International Metals Park, Ohio, copyright 1987 Cyril A. Dostal Senior Ed, pp. 105-168 and 497-533, and xe2x80x9cPolyesters and Their Applicationsxe2x80x9d by Bjorksten Research Laboratories, Johan Bjorksten (pres.) Henry Tovey (Ch. Lit. Ass.), Betty Harker (Ad. Ass.), James Henning (Ad. Ass.), Reinhold Publishing Corporation, New York, 1956. Processing techniques include resin transfer molding; sheet molding; bulk molding; pultrusion; injection molding, including reaction injection molding (RIM); atmospheric pressure molding (APM); casting, including centrifugal and static casting open mold casting; lamination including wet or dry lay up and spray lay up; also included are contact molding, including cylindrical contact molding; compression molding; including vacuum assisted resin transfer molding and chemically assisted resin transfer molding; Seeman""s Composite Resin Infusion Manufacturing Processing (SCRIMP); open molding, continuous combination of resin and glass; and filament winding, including cylindrical filament winding.
A sheet molding compound may comprise for example 1) about 15 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts by weight of an acryloyl monomer; 4) about 0.25 to about 4 parts by weight of a curing catalyst, preferably an azo or peroxide compound such that the total parts of the components 1-4 equal 100 parts; 5) about 100 to about 250 parts of a filler; and 6) about 10 to about 400 parts of a fibrous filler, preferably about 1xe2x80x3 chopped fibrous filler, more preferably 1xe2x80x3 chopped glass fiber. The sheet molding compound may further comprise 7) about 2 to about 20 parts of a polymeric filler. The sheet molding compound may be cured by heating at temperatures of about 120xc2x0 C. to about 170xc2x0 C., preferably about 130xc2x0 C. to about 160xc2x0 C., under pressures of about 100 to about 5,000 psi and preferably from about 500 to about 3,000 psi. An uncured sheet molding compound may be also cured by means of electron beam or UV irradiation, or a combination of these processes.
An injection molding composition may comprise 1) about 15 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts of an acryloyl monomer, preferably an acryloyl monomer containing 2, 3, 4, or 5 acryloyl groups per molecule; 4) about 0.25 to about 4 parts by weight of a curing catalyst, preferably an azo or peroxide compound; such that the total of the components 1-4 equal 100 parts by weight; 5) about 100 to about 250 parts by weight of a filler; and 6) about 10 to about 400 parts by weight of a fibrous filler, preferably about 1xe2x80x3 chopped fibrous filler, and more preferably about 1xe2x80x3 chopped glass fiber. The injection molding composition may further comprise 7) about 2 to about 20 parts of a polymeric filler. The injection molding composition may be cured by heating at temperatures of about 120xc2x0 C. to about 170xc2x0 C., preferably about 130xc2x0 C. to about 160 xc2x0 C., under pressures of about 100 to about 5,000 psi, preferably about 500 to about 3,000 psi.
A bulk molding compound may comprise, for example, 1) about 15 to about 45 parts by weight a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 weight of an acryloyl monomer; 4) about 0.25 to about 4 parts by weight of a curing catalyst, preferably an azo or peroxide compound, such that the total of components 1-4 equals 100 parts by weight; 5) about 100 to about 250 parts by weight of a filler; and 6) about 10 to about 400 parts by weight of a fibrous filler, preferably about 1xe2x80x3 chopped fibrous filler, more preferably chopped glass, graphite, or aramid fiber or a combination thereof, typically xe2x85x9xe2x80x3-xc2xdxe2x80x3 in length. The bulk molding compound may further comprise 7) about 2 to about 20 parts by weight of a polymeric filler. The bulk molding compound may be cured by heating the composition at a temperatures of about 120xc2x0 C. to about 170xc2x0 C., preferably about 130xc2x0 C. to about 160 xc2x0 C., under a pressure of about 100 to about 5,000 psi, preferably about 500 to about 3,000 psi. An uncured bulk molding compound may be also cured by means of electron beam or UV irradiation, or a combination of these processes.
A resin transfer molding composition may be used to produce a cured article. Such a composition may comprise, for example, 1) about 10 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts by weight of an acryloyl monomer, preferably an acryloyl monomer containing 2, 3, 4, or 5 acryloyl groups per molecule; 4) about 0.5 to about 4 parts by weight of a curing catalyst, preferably an azo or a peroxide compound; such that the total of components 1-4 equals 100 parts by weight; and 5) about 10 to about 800 parts of a fibrous filler, preferably glass, graphite, aramid, or ceramic, or a combination thereof. The composition may further comprise 6) about 5 to about 250 parts by weight of a filler and further may contain 7) about 1 to about 20 parts by weight of a polymeric filler. Curing of the composition may utilize a pressure of about 100 to about 5,000 psi and an energy source including heat, electron beam irradiation, UV irradiation, or a combination comprising at least one of the foregoing sources.
A pultrusion composition may comprise, for example, 1) about 10 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts by weight of a multifunctional acrylate; 4) about 0.5 to about 4 parts by weight of a curing catalyst, preferably a peroxide, such that the total of components 1-4 equals 100 parts by weight; and 5) about 10 to about 400 parts by weight of a fibrous filler, preferably continuous glass, carbon, or aramid fiber, or a combination thereof. The pultrusion composition may further comprise 6) about 1 to about 20 parts by weight of a polymeric filler and/or 7) about 5 to about 250 parts by weight of a filler.
A filament wound article may be produced from a composition comprising 1) about 15 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts by weight of an acryloyl monomer having 2, 3, 4, 5, or more acryloyl groups; 4) about 0.5 to about 4 parts by weight of a peroxide curing agent. The composition for filament winding may further comprise 5) about 1 to about 20 parts by weight of a polymeric filler and/or 7) about 5 to about 250 parts of a filler. This composition for filament winding may be impregnated into 6) about 10 to about 500 parts by weight of a fibrous filler, preferably glass, carbon, or aramid fibers, or a combination thereof.
A compression molding composition may comprise, for example, 1) about 15 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts by weight of an acryloyl monomer having 2, 3, 4, 5, or more acryloyl groups; 4) about 0.5 to about 4 parts by weight of a peroxide curing agent; wherein the total of components 1-4 is 100 parts by weight; 5) about 5 to about 800 parts by weight of a filler. The compression molding composition may further comprise 6) about 1 to about 20 parts by weight of a polymeric filler and/or 7) about 10 to about 500 parts of a fibrous filler.
Another compression molding composition may comprise 1) about 15 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts by weight of an acryloyl monomer having 2, 3, 4, 5, or more acryloyl groups; 4) about 0.5 to about 4 parts by weight of a peroxide curing agent; wherein the total of components 1-4 is 100 parts by weight. The compression molding composition may further comprise 5) about 10 to about 800 parts by weight of a fibrous filler and/or 6) about 1 to about 20 parts by weight of a polymeric filler and/or and 7) about 5 to about 250 parts of a filler.
A spray-layup process may be used to produce a cured article. In such a process fiber is chopped in a hand-held gun and fed into a spray of catalyzed resin directed at the mould. The deposited materials are left to cure under standard atmospheric conditions. A spray lay-up composition may comprise, for example, 1) about 15 to about 45 parts by weight of a methacrylate-capped poly(arylene ether); 2) about 40 to about 65 parts by weight of an alkenyl aromatic monomer; 3) about 5 to about 25 parts by weight of an acryloyl monomer having 2, 3, 4, 5, or more acryloyl groups; 4) about 0.5 to about 4 parts by weight of a curing catalyst, preferably a peroxide blended with a transition metal salt and an amine as described above; wherein the total of components 1-4 is 100 parts by weight. The spray lay-up composition may further comprise 5) about 1 to about 20 parts by weight of a polymeric filler and/or 6) about 5 to about 100 parts by weight of a filler. Such a composition may be combined by spraying into a spray of 10-500 parts by weight of a chopped fibrous filler, preferably glass and more preferably E-glass.
The inventive composition may be used to impregnate fibrous reinforcement clad with copper to form an electrical circuit boards offering excellent dielectric and thermal properties, and accelerated rates of polymerization in formation of the poly (arylene ether) compositions. Moreover, such poly(arylene ether) compositions may also be flame-retardant.
Molding compositions and laminate compositions are only a few of the many potential applications possible for the composition. Potential applications for the use of the composition include those known to the art for thermoplastics and thermosetting resins, particularly those having properties such as high Tg, toughness, excellent dielectric properties, and good flow properties.
Further contemplated is the curing of fiber-reinforced compositions such that they are adhered to the surface of other materials to form composite articles. Such composite articles, having, for example, honeycomb and foam structures, may be found in Engineered Materials Handbook, Volume 1, Composites, ASM International Metals Park, Ohio, copyright 1987 Cyril A. Dostal Senior Ed., pages 722-728. Thus, by curing of the inventive composition in contact with other materials more complex structures may be formed. Such other materials include foams such as PVC foam, polystyrene foam, polyurethane foam, polypropylene foam, polyethylene foam, and the like; wood including balsa, cedar, and the like; and materials such as COREMAT(copyright) or SPHERETEX(copyright), which are materials consisting of a low density felt-like resins filled with low density microspheres. Also, the compositions may be cured onto the surface of honeycomb structures comprised of organic resins such as polyimides, including NOMEX(copyright), metals such as aluminum, or the like.
Applications include, for example, acid bath containers; neutralization tanks; aircraft components; bridge beams; bridge deckings; electrolytic cells; exhaust stacks; scrubbers; sporting equipment; stair cases; walkways; automobile exterior panels such as hoods and trunk lids; floor pans; air scoops; pipes and ducts, including heater ducts; industrial fans, fan housings, and blowers; industrial mixers; boat hulls and decks; marine terminal fenders; tiles and coatings; building panels; business machine housings; trays, including cable trays; concrete modifiers; dishwasher and refrigerator parts; electrical encapsulants; electrical panels; tanks, including electrorefining tanks, water softener tanks, fuel tanks, and various filament-wound tanks and tank linings; furniture; garage doors; gratings; protective body gear; luggage; outdoor motor vehicles; pressure tanks; printed circuit boards; optical waveguides; radomes; railings; railroad parts such as tank cars; hopper car covers; car doors; truck bed liners; satellite dishes; signs; solar energy panels; telephone switchgear housings; tractor parts; transformer covers; truck parts such as fenders, hoods, bodies, cabs, and beds; insulation for rotating machines including ground insulation, turn insulation, and phase separation insulation; commutators; core insulation and cords and lacing tape; drive shaft couplings; propeller blades; missile components; rocket motor cases; wing sections; sucker rods; fuselage sections; wing skins and flairings; engine narcelles; cargo doors; tennis racquets; golf club shafts; fishing rods; skis and ski poles; bicycle parts; transverse leaf springs; pumps, such as automotive smog pumps; electrical components, embedding, and tooling, such as electrical cable joints; wire windings and densely packed multi-element assemblies; sealing of electromechanical devices; battery cases; resistors; fuses and thermal cut-off devices; coatings for printed wiring boards; casting items such as capacitors, transformers, crankcase heaters; small molded electronic parts including coils, capacitors, resistors, and semiconductors; as a replacement for steel in chemical processing, pulp and paper, power generation, and wastewater treatment; scrubbing towers; pultruded parts for structural applications, including structural members, gratings, and safety rails; swimming pools, swimming pool slides, hot-tubs, and saunas; drive shafts for under the hood applications; dry toner resins for copying machines; marine tooling and composites; heat shields; submarine hulls; prototype generation; development of experimental models; laminated trim; drilling fixtures; bonding jigs; inspection fixtures; industrial metal forming dies; aircraft stretch block and hammer forms; vacuum molding tools; flooring, including flooring for production and assembly areas, clean rooms, machine shops, control rooms, laboratories, parking garages, freezers, coolers, and outdoor loading docks; electrically conductive compositions for antistatic applications; for decorative flooring; expansion joints for bridges; injectable mortars for patch and repair of cracks in structural concrete; grouting for tile; machinery rails; metal dowels; bolts and posts; repair of oil and fuel storage tanks, and numerous applications in which a structural or dielectric resin or composite such as an polyester, vinyl ester, allylic, epoxy, cyanate ester, or polyphenylene ether resin or blend may be used.
The invention is further illustrated by the following non-limiting examples.
For the following Examples, the poly(2,6-dimethylphenyl ether) (PPE) was obtained from the General Electric Company. Calcium carbonate was obtained from Omya Corporation as OMYACARB(copyright) 5. Glass, either as continuous glass mat or chopped xc2xd inch fibers, was obtained from Owens Corning Fiberglass Corporation. All reagents were obtained from Aldrich Chemical Company unless otherwise specified. Gel permeation chromatography (GPC) was performed using a Waters Gel Permeation
Chromatograph with a bank of PHENOMENEX(copyright) Phenogel 105, 104, and 500 Angstrom columns. A polymer solution (100 ml, approximately 0.3% by weight) was injected and the polymer eluted from the column using a chloroform solvent containing 0.5% ethanol at a flow rate of 1.5 ml/min. Elution was monitored using a UV detector set at 254 nm. The columns were calibrated using polystyrene standards (2,030 to 860,000 g/mol). 1H-NMR spectra were collected on a GE QE-300 MHz NMR spectrometer using CDCl3 solvent and a tetramethylsilane (TMS) internal standard. Methacrylic endcap concentration ([MAA]) was determined by 1H-NMR analysis by comparison of the integrals of the methyacrylic vinyl hydrogens to those of the aromatic hydrogens of the PPE repeat unit. 31P-NMR spectra were recorded on a GE GN-500 MHz spectrometer with hydroxyl endgroup concentration ([OH]) performed as described by P. Chan, D. S. Argyropolis, D. M. White, G. W. Yeager, and A. S. Hay, Macromolecules, 1994, volume 27, pages 6371 ff. Intrinsic viscosity (IV) measurements were performed at 25xc2x0 C. from chloroform solutions using an Ubbelohde viscometer.
Resin Transfer molded samples were prepared using a Radius FlowWare RTM 2100 Injector, and the resin injected to a 10xe2x80x3xc3x9710xe2x80x3xc3x970.125xe2x80x3 plaque mold under 200 psi pressure. The glass transition temperatures (Tg) and coefficients of thermal expansion (CTE) were determined according to ASTM D6341. Decomposition onset temperatures in nitrogen and air were measured by thermogravimetric analysis (TGA) by placing resin samples of approximately 3 mm3 in size in a platinum pan and performing the test using a TA Instruments TGA2950 run at atmospheric pressure under a constant flow (60 ml/min) of nitrogen or air. The temperature was increased at 20xc2x0 C./min from 30 to 700xc2x0 C.
Flexural modulus and flexural strength values were measured according to ASTM D6272. Fracture toughness (K1c) was measured according to ASTM 5045. Morphology was determined by transmission electron microscopy (TEM). Transmission electron micrographs (TEMs) were obtained on specimens sectioned with a diamond knife on an ultramicrotome. The sections were stained using RuO4 vapor and micrographs were taken on a Philips CM1000 TEM operated at 100 KeV. Dynamic Mechanical Analysis (DMA) was performed using a Rheometrics Dynamic Spectrometer 7700. Samples having approximate dimensions of 3.2xc3x9764xc3x9713 mm were analyzed from 25 to 230xc2x0 C., at a heating rate of 5xc2x0 C./min. Samples approximately 3.2xc3x9764xc3x9713 mm in size were first notched and then a sharp crack was initiated with a razor blade. Load to failure was determined using an Instron 8500 Plus servo-hydraulic test instrument. Flexural Properties were determined in accordance with ASTM D790. Dielectric constants (Dk) and dissipation factors (Df) were measured according to ASTM D150-95.